The present invention relates to an automatic pressure control device of a side seal plate in a seal mechanism of a high pressure steamer for continuous wet-heat treatment of a cloth at higher temperatures.
There has been disclosed a seal mechanism of a high pressure steamer comprising a pair of seal rubber rolls provided respectively above the cloth inlet and outlet of a high pressure steamer body and a seal frame or block to support the seal rubber rolls freely rotatable. The opening left at the side of the space surrounded with the seal rolls and the seal frame is sealed with the aid of a side seal plate. However, since the seal rolls are heated tolerably in wet-heat treatment, they expand unavoidably to some extent. Therefore, in contacting the side seal plate closely to the seal rolls and the seal frame prior to the operation of the high pressure steamer, severe friction is caused to occur between the side seal plate and the seal rubber rolls due to the thermal expansion of the seal rolls in operating the high pressure steamer, thus rendering the operation impossible. Inversely, in forming a gap between the said members previously in considering the expansion of the seal rubber rolls, the interior of the steamer body can difficultly be elevated sufficiently due to the leakage of the wet-heat, thus causing such a trouble that a long time is needed until a normal operation can be done.
To solve such a drawback, the present applicants have recently proposed an automatic control device of a side seal plate in such a seal mechanism of a high pressure steamer as above-mentioned. The device comprises providing a pressure-push rod for contacting the side seal plate to the sides of the seal rubber rolls and the seal frame, a pressure-sensitive means for pushing the pressure-push rod toward the sides of the seal rolls and the seal frame in accordance with the inner pressure of the high pressure steamer body, and a plurality of metal springs for pressure-pushing the side seal plate to the sides of the seal rolls and the seal frame with a suitable pressure even when the said pressure-sensitive means is not acting. However, this device needs a pressure-sensitive means movable according to the inner pressure of the steamer body for pushing the side seal plate, so that not only the device becomes complicated in total but also its control is troublesome.